• Structural Engineering and Mechanics
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• v.9 no.5
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• pp.417-432
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• 2000

A comprehensive analytic study has been conducted to investigate the instability problems of metal-plate-connected (MPC) joints in light frame trusses. The primary objective in this study is to determine the governing factors that constitute the buckling of the metal connectors and their effects on the structural response of joints. Another objective is to recommend design curves for the daily structural design of these joints. The numeric data presented in this paper has emerged from a broad base that was founded on over 350 advanced computer simulations, and was supported by available experimental results obtained by others. This basic-to-applied research includes practical engineering parameters such as size of gaps, shear lengths, gauge (plate thickness) of connectors, size of un-braced areas, failure modes, and progressive disintegration of joints. Square-end members have been emphasized though the results cover the custom-made fitted joints. The results indicate that chord shears cause and dominate the buckling of MPC joints, and the shear length has a more pronounced effect than the size of gaps. Further, large gauges and small un-braced areas improve the buckling response. Several practical recommendations have been suggested throughout the paper such as keeping the ratio of gap/shear length below 3/4 for improving the buckling strength. The study reveals that multi-area joints should not be simplified as single web-to-chord MPC joints such as keeping the ratio of gap/shear length below 3/4 for improving the buckling strength, even where one web is in tension and the other in compression. Finally, the results obtained from this study favorably agree with experimental data by others, and the classic buckling theories for other structural components.

• Journal of Oral Medicine and Pain
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• v.21 no.1
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• pp.103-113
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• 1996

The author examined the clinical signs and symptoms , routine radiographs, laboratory test and bone scan in 73 subjects with TMJ disorders and studied the responses of clinical test on patients, the distribution of signs and symptoms of joints, the simple uptake rate(SUR) of affected joints , the SUR of subclassified groups of TMJ disorders, active joints of subclassified groups of TMJ disorders and the SUR of joints with noises. The obtained results were as follows : 1. The percentage of joint pain on palpation, joint noises joint pain on function, mandibular dysfunction and active finding of bone scan in aptients with TMJ disorders were higher 2. The SUR was higher in joints affected by joint pain on function, joint pain on palpation, mandibular dysfunction and creptius. 3. The SUR of osteoarthrosis was the lowest. 4. The percentage of active joints were the highest in joints with discdisplacement without reduction, and followed by osteoarthritis, and disc displacement with reduction. 5. The SUR of TMJ showing joint noises only was lower.

• Journal of the Korean Society of Safety
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• v.33 no.5
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• pp.70-77
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• 2018

In this study, the reinforced methods of joints were proposed to improve the structural performance of the enhanced spun reinforced concrete piles with joints. To verify the proposed methods, flexure performance was validated by finite element analysis considering both material and contact nonlinearity. Based on the previous study and those results of the analysis, it is concluded that the structural performance of the current joints system for the enhanced spun RC piles can be enhanced by applying the reinforced joints composed of extended circular band plates and studs. This proposed method showed the nearest structural behavior to the enhanced spun RC piles without joints. This numerical study will be used to further experimental study on the enhanced spun RC piles with reinforced joints.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1996.10a
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• pp.249-257
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• 1996

Dynamic Analysis of Precast Concrete Large Panel Structures with Horizontal Joints The damage in precast large panel structures subjected to destructive earthquakes is generally localized in the joints. Particularly, the horizontal joints influence on the stability and integrity of the overall structure. In this research a dynamic analysis was carried out by the macro model that idealized the horizontal joints as inelastic-nonlinear spring systems. It is capable of simulating the behavior of precast concrete structures using the mathematical model. As a result of the dynamic parametric study for the case of 0.12g peak base accelerations, it is found that all joints behave elastically for sliding and opening and that all forces are well distributed without excessive local concentration on my horizontal joints.

• Proceedings of the KWS Conference
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• 2005.06a
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• pp.262-264
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• 2005

This paper is concerned with a fracture strength study of composite adhesive lap joints. The tests were carried out on specimen joints manufactured hybrid stacked joints such as the polyester and bamboo natural fiber layer. The main objective of the work was to test the fracture strength using hybrid fiber composites with a polyester and bamboo natural fiber layer adjacent to the spew fillet of adhesive bonded joints and hybrid stacked joints. The results are presented using tensile-shear strength graph and finite element analysis. The failure mechanisms are discussed in order to explain that spew fillet at the end of the overlap reduces greatly the adhesive shear and effects the tensile-shear strength in hybrid stacked joints.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.190-191
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• 2019

In complex waterproofing method, the stability of the joint is an important factor. The joints should not be broken for repeated movements and tensile forces. Therefore, we tried to confirm the stability of joints in newly developed joints and general joints. Repeated fatigue resistance performance tests and joint tensile strength tests were carried out on four types of joints. The fatigue resistance performance test showed no abnormality in all four types. It was confirmed that the newly developed top-down joint has higher stiffness than existing joints.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.208-213
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• 2002

When a thermoset conductive adhesive joints are subjected to the thermal cycles, the thermal stresses are developed around the joints. Most of in-plane, hi-axial components of these residual stresses induces large tensile peel stresses and weakens adhesive joints. Also these stresses vary with thermal cycles, and result in thermal fatigue loading and debonding propagation. In this study, the thermal ratchetting effect in conductive adhesive joints are evaluated by the finite element analysis with the viscoelastic material model. In order to Investigate the relationship between thermal ratchetting and glass transition temperature, the mathematical material model has been developed experimentally by dynamic mechanical analysis. These material models are implemented to the finite element analysis with thermal loading cycles. And the stress profiles around the conductive adhesive joints are calculated. It has been observed that the thermal ratchetting occurs when the maximum temperature of thermal cycles is above the glass transition temperature. The peel and shear stress components increase as the thermal loading time increases. This will contributes to thermal fatigue fracture of the joints.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.2
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• pp.92-101
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• 1997

In this paper, modeling methods for 2D joints are proposed. Earlier methods for modeling 2D joints that use geometric relationships may not consider irregularities or dynamic effects of joints. In any case, it is important to consider irregularities or dynamic effects. To consider those, methods that use dynamic contacts are proposed. With the method, 2D joints that have irregularities or dynamic effects amy be model- ed and analyzed. 2D joints that are developed are revolute, translational, gear and point-follower joint.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.269-276
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• 2001

Tubular structures are widely used for offshore platforms and truss type structures. In this paper, nonlinear finite element analysis is used to assess the static strength of stiffened tubular T-joints subjected to compressive brace loading. This joints was modelled with and without internal ring stiffener According to variation of ring geometries, the effect of ring stiffener for T-joints are investigated. Internal ring stiffener is found to be efficient improving ultimate strength of tubular joints. Relations of ring thickness and axial strength are observed considering geometric parameters of ring stiffeners.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1992.10a
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• pp.45-51
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• 1992

Trilinear analytical models representing the behavior of composite beam-steel column joints and seismic shear design method for the joints are presented. Emphasis is placed on the effect of the concrete slab on the behavior of the joints. To validate the analytical models, Comparisons with the experimental results are made. Application of the proposed method to seismic shear design of joints improves the seismic resistance of the steel frame with composite slab.